DAO 21:233-238 (1995)  -  doi:10.3354/dao021233

Aphanomyces species associated with epizootic ulcerative syndrome (EUS) in the Philippines and red spot disease (RSD) in Australia: preliminary comparative studies

Callinan RB, Paclibare JO, Bondad-Reantaso MG, Chin JC, Gogolewski RP

Fungi morphologically consistent with class Oomycetes were recovered on primary culture from 20 of 22 ulcers on 21 fish with epizootic ulcerative syndrome (EUS) collected from 5 sites in the Philippines. Eleven primary isolates, and the unifungal cultures derived from them, were identified as Aphanomyces spp.; the remaining 9 primary isolates were lost through contaminant overgrowth. The Aphanomyces isolates were morphologically and culturally indistinguishable from those reported from red spot disease (RSD) in Australia. Comparison of 4 representative Aphanomyces isolates from Australian fish with RSD and 3 representative Aphanomyces isolates from Philippine fish with EUS, using SDS-PAGE (sodium dodecyl sulphate polyacrylamide gel electrophoresis), revealed similar peptide banding profiles, indicative of a single Aphanomyces species. These findings, combined with epizootiological and pathological similarities between EUS and RSD, suggest the 2 syndromes are identical, and that a single Aphanomyces sp. may be the primary infectious cause.


Aphanomyces . Ulcer . EUS . Philippines . Australia


Full text in pdf format